Substrate support with electrostatic chuck having dual temperature zones

Abstract

An electrostatic chuck for receiving a substrate in a substrate processing chamber comprises a ceramic puck having a substrate receiving surface and an opposing backside surface with a plurality of spaced apart mesas. An electrode is embedded in the ceramic puck to generate an electrostatic force to hold a substrate. Heater coils located at peripheral and central portions of the ceramic puck allow independent control of temperatures of the central and peripheral portions of the ceramic puck. The chuck is supported by a base having a groove with retained air. The chuck and base can also have an overlying edge ring and clamp ring.

1. An electrostatic chuck for receiving a substrate in a process chamber, the chuck comprising:
 (a) a ceramic puck comprising a substrate receiving surface and an opposing backside surface, the backside surface comprising a plurality of spaced apart mesas; 
 (b) a plurality of heat transfer gas conduits traversing the ceramic puck and terminating in ports on the substrate receiving surface to provide heat transfer gas to the substrate receiving surface; 
 (c) an electrode embedded in the ceramic puck to generate an electrostatic force to retain a substrate placed on the substrate receiving surface; and 
 (d) first and second heater coils that are radially spaced apart, concentric about one another, and embedded in the ceramic puck, the first heater coil located at a peripheral portion of the ceramic puck and the second heater coil located at a central portion of the ceramic puck. 
 
     
     
       2. A chuck according to  claim 1  wherein the first and second heater coils are arranged side by side and substantially in the same plane. 
     
     
       3. A chuck according to  claim 1  wherein the first and second heater coils each comprise a resistive heating element comprising molybdenum. 
     
     
       4. A chuck according to  claim 1  wherein the first and second heater coils each comprise an electrical resistance sufficiently high to maintain the substrate receiving surface of the ceramic puck at temperatures of from about 80 to about 250° C. 
     
     
       5. A chuck according to  claim 1  wherein the ceramic puck comprises at least one of aluminum oxide, aluminum nitride, silicon oxide, silicon carbide, silicon nitride, titanium oxide, zirconium oxide, and mixtures thereof. 
     
     
       6. A chuck according to  claim 1  wherein the mesas on the backside surface on the ceramic puck each comprise cylindrical mounds. 
     
     
       7. A chuck according to  claim 1  wherein the ceramic puck comprises a peripheral ledge to receive a clamp ring that forms a seal around the ceramic puck. 
     
     
       8. A chuck according to  claim 1  further comprising first and second optical temperature sensors embedded in the ceramic puck, with the first sensor positioned at the central portion of the ceramic puck and the second sensor positioned at the peripheral portion of the ceramic puck. 
     
     
       9. A chuck according to  claim 8  wherein the optical temperature sensors comprise a phosphorous layer in front of an optical fiber, the phosphorous layer being embedded in a copper tip. 
     
     
       10. A chuck according to  claim 8  wherein the optical temperature sensors comprise a temperature isolation jacket. 
     
     
       11. A chuck according to  claim 1  wherein the substrate receiving surface of the ceramic puck comprises a plurality of raised plateaus, the raised plateaus being separated by a pattern of grooves. 
     
     
       12. A chuck according to  claim 11  wherein the raised plateau comprise second mesas on the raised plateau. 
     
     
       13. A chuck according to  claim 11  wherein the pattern of grooves comprise radial and circular arms which are interconnected to one another. 
     
     
       14. A chuck according to  claim 12  wherein the raised plateaus comprise from about 10 to about 1000 second mesas. 
     
     
       15. A chuck according to  claim 12  wherein the second mesas have an average height of from about 5 to about 50 microns. 
     
     
       16. A chuck according to  claim 12  wherein the second mesas have a diameter of from about 0.5 to about 5 mm. 
     
     
       17. An electrostatic chuck for receiving a substrate in a process chamber, the chuck comprising:
 (a) a ceramic puck comprising a substrate receiving surface and an opposing backside surface, a peripheral ledge, and an opposing backside surface, the opposing backside surface having a plurality of spaced apart mesas thereon; 
 (b) a plurality of heat transfer gas conduits traversing the ceramic puck and terminating in ports on the substrate receiving surface to provide heat transfer gas to the substrate receiving surface; 
 (c) an electrode embedded in the ceramic puck to generate an electrostatic force to retain a substrate placed on the substrate receiving surface; and 
 (d) first and second heater coils that are radially spaced apart, concentric about one another, and embedded in the ceramic puck, the first heater coil located at a peripheral portion of the ceramic puck and the second heater coil located at a central portion of the ceramic puck, the first and second heater coils being independently controllable. 
 
     
     
       18. A chuck according to  claim 17  wherein the peripheral ledge comprises first and second steps. 
     
     
       19. A chuck according to  claim 18  wherein the second step is radially outward of, and lower than, the first step. 
     
     
       20. A chuck according to  claim 17  wherein the first and second heater coils are arranged side by side and substantially in the same plane. 
     
     
       21. A chuck according to  claim 17  wherein the substrate receiving surface of the ceramic puck comprises a plurality of raised plateaus, the raised plateaus being separated by a pattern of grooves. 
     
     
       22. A chuck according to  claim 21  wherein the raised plateaus comprise a plurality of second mesas thereupon. 
     
     
       23. A chuck according to  claim 17  wherein the first and second heater coils each comprise a resistive heating element comprising molybdenum. 
     
     
       24. A chuck according to  claim 22  wherein the ceramic puck comprises aluminum oxide, aluminum nitride, silicon oxide, silicon carbide, silicon nitride, titanium oxide, zircomium oxide, or mixtures thereof. 
     
     
       25. An electrostatic chuck comprising:
 (a) a ceramic puck comprising a substrate receiving surface comprising a plurality of raised plateaus separated by a pattern of grooves, an opposing backside surface comprising a plurality of spaced apart mesas, and a peripheral ledge having first and second steps; 
 (b) a plurality of heat transfer gas conduits traversing the ceramic body and terminating in ports on the substrate receiving surface to provide heat transfer gas to the substrate receiving surface; 
 (c) an electrode embedded in the ceramic puck to generate an electrostatic force to retain a substrate placed on the substrate receiving surface; and 
 (d) first and second heater coils embedded in the ceramic puck, the heater coils being radially spaced apart concentric about one another, and in the same plane, the first heater coil located at a peripheral portion of the ceramic puck and the second heater coil located at a central portion of the ceramic puck. 
 
     
     
       26. A chuck according to  claim 25  wherein the first and second heater coils each comprise a resistive heating element comprising molybdemum. 
     
     
       27. A chuck according to  claim 25  wherein the ceramic puck comprises at least one of aluminum oxide, aluminum nitride, silicon oxide, silicon carbide, silicon nitride, titanium oxide, zircomium oxide, and mixtures thereof. 
     
     
       28. A chuck according to  claim 25  wherein the mesas comprise cylindrical mounds. 
     
     
       29. A chuck according to  claim 25  further comprising first and second optical temperature sensore embedded in the ceramic puck, with the first sensor positioned at the central portion of the ceramic puck and the second sensor positioned at the peripheral portion of the ceramic puck. 
     
     
       30. A chuck according to  claim 29  wherein the optical temperature sensors comprise a phosphorous layer in front of an optical fiber, the phosphorous layer being embedded in a copper tip. 
     
     
       31. A chuck according to  claim 25  wherein the raised plateaus comprise a plurality of second mesas thereupon. 
     
     
       32. A chuck acording to  claim 31  wherein the raised plateaus comprise from about 10 to about 1000 second mesas. 
     
     
       33. A chuck according to  claim 31  wherein the second mesas have an average height of from about 5 to about 50 microns. 
     
     
       34. A chuck according to  claim 31  wherein the second mesas have a diameter of from about 0.5 to about 5 mm.